Ore-treating apparatus.



A. L. B'LOMHELD.

@RE TREATING APPARATUS.

APPLICAHQN FILED DEC- 5,?11- 1,294,?5Q Patented Feb. 18, 1919.

2 SHEETSSHEEI I.

INVENTOR L. BL OMFIEL. 0.

A. L. BLOMFIELD. ORE TREATING APPARATUS. APPLICATION FILED DEC. 5. I917.

Patented Feb. 18, 1919.

2 SHEETS-SHEEI 2.

L INVENTOR' ALBLoMF/ELD ALFRED L. BLOMFIELD, or DENVER, COLORADO, nssrenon TO THE Donn COMPANY, a

. conromrron or NEW JERSEY.

ORE-TREATING APPARATUS.

Specification of Letters Patent.

Patented Feb. 18, 1919.

Continuation in part of application Serial No. 188,468, filed August 27, 1917. This application filed December 5, 1917. Serial No. 205,563.

To all whom it may concern:

Be it known that I, ALFRED L. BLOMFIELD, a subject of George V, King of England, residing at Denver, in the county of Denver and State of Colorado, have invented certain new and useful Improvements in Ore- Treating Apparatus, of which the following is a specification.

This invention relating to improvements in ore-treating apparatus, is continuation in part of my application for Patent, Number 188,468, filed August 27, 1917, and its primary object is to provide in combination with apparatus for the classification of comminuted ores, means for regulating the feed thereto by and in proportion to a resistance presented by the oversize to its movement toward a point of discharge.

My invention is particularly adapted for use in connection with apparatus of the type in which the aqueous material is divided by the subsidence of its heavy and coarse constituents relative to a point of overflow at which the fines which are held in suspension in the liquid, are discharged, and in which the settling oversize is mechanically impelled toward an outlet which for dewatering purposes is preferably disposed above the liquid-level determined by the overflow.

By the automatic regulation of the feed in proportion to a resistance offered by the oversize to the action of the impelling mechanism, an overload is avoided and the classifier is constantly maintained at when its point of greatest efiiciency.

In case the classifier is connected in a closed circuit with a comminuting apparatus, as has been shown in the accompanying drawings, it is the return movement of the oversize that regulates the feed to the circuit to automatically maintain a constant and regular operation of both the classifier and the comminuting apparatus and insure a product of uniform character.

In the accompanying drawings I have shown my invention as applied to a classifier of the Dorr type which is connected in a closed circuit with a grindingmachine of the ballor tube-mill type.

I desire it understood, however, that my invention is not confined to any special classifying or settling apparatus, nor is it limited to the use of any particular means for the conveyance of the oversize or the regulation of the feed by the resistance presented to its movement to the point of its discharge and the-closed circuit shown in the drawings is merely illustrative of one of many uses for which my invention is adapte It should also be understood that while I have shown and described the feed-regulating apparatus as being composed of an association of'electrical devices, the objects of my invention may be attained with equal efiiciency by the use of a mechanical operatin mechanism.

'eferring to the drawings in the several views of which like parts have been similarly designated,

Figure 1 represents a plan view of a closed circuit grinding system includinga cllaissiifier to which my invention has been ap- P e Fig. 2, a section taken along the line 2-2, Fig. 1, and

Fig. 3, a section along the line 33, Fig. 1.

he reference character 2 designates a classifier of the Dorr type, and 3 a grinding mill of the ballor tube-mill type.

The material supplied through a hopper 4 is by the movement of an endless belt 5 conveyed to a box 6 from which it is lifted by a rotary scoop 7 and fed into the feedtrunnion of the grinding mill.

The ground product discharged from the grinding-mill through the trunnion at its opposite end, is by means of a chute 8 conveyed to the feed-end of the classifier and the coarse product or oversize obtained in the operation of the classifier is by means of a chute 9 returned to the box 6 and fed into the ball-mill with the fresh material supplied through the hopper 4.

The classifier hereinbefore referred to consists in its simplest form of a trough-shaped settling chamber 10 the bottom 12 of which slopes from its feed-end upwardly to a point above the liquid level determined by an overflow 13 at its lower end.

The launder 8 discharges the feed to the classifier into a distributing box 14:, the liquid and suspended fines are constantly discharged across the overflow into a launder 15, and the coarser matter or oversize which settles to the bottom of the trough is mechanically impelled to an outlet 16 at the upper end of the classifier above the li uid-level determined by the overflow.

he mechanism for moving the material upwardly along the inclined bottom of the trough consists in its preferred form of a pair of rakes 17 which are suspended for reciprocation and which are operatively connected with a crank-wheel 18 on a driving shaft 19 by means of a pitman'20. I I It is the resistance to the impellingvmovement of the rakes that in the present classi- .fier is utilized for the operation of the appliance or appliances by which the feed to the circuit of which the classifier is a part, is automatically regulated.

In the construction shown in the drawings, the shaft 19 is by means of a belt 21 connected with an electric motor 22 and one of the pulleys 23 upon which the endless feed belt is supported, is by the use of a belt 24, connected with a second electric motor 25.

An ammeter 26 connected in the circuit 27 of the first-mentioned motor has a circuit} breaking appliance which in the illustrative form shown in the drawings comprises astationary contact 28 and a pivoted arm 29 adapted to be moved into engagement therewlth by the movement of the hand .30 when the amperage of the current passing through thecircuitexceeds a predetermined amount.

The two contact-members of the circuitbreaker are connected at opposite sides of a' break in ashunt 31 of the main circuit, the current-flow through which controls the operation of a second circuit breaker which in its simplest form consists of a solenoid 32 and a pair of contacts 33 which under normal conditions are electrically connected by a bridge 3 on the reciprocating armature.

thereof.

The contact members of the second clrcuit breaker are connected at opposite sides of a break in one of the conductors 35 which sistance to the driving action of the motor 22 is increased, the consequent rise in amperage of the current passing through the motor-circuit will cause a movement of thehand of the ammeter and a. corresponding movement of the contact arm of the primary circuit breaker toward the relatively stationary contact 28. a When by engagement of the contact members of the circult breaker the shunt circuit 31 is completed, the current flow consequent thereto energizes the solenoid of the second circuit breaker which by the movement of its armature disconnects the contacts 33. v

The current is thereby shunted through the resistance coil 36 with the result that the current flow through the motor 25 is retarded. a a

The reduced current-flow and correspondingl reduced rate of rotation of the motor sha retards the movement of the feed belt material settling upon the bottom of the inclined trough, to the impelling action of the reciprocating1 rakes which constantly move it toward t e outlet at the upper end of the trough. i If by an increased feed to the classifier the quantity of material. settling on the bottom thereof exceeds a predetermined amount, the consequent rwistance will increase the load upon the motor and the ini-' tial feed of material is proportionately reduced; "Overloading ofthe classifier or of the classifier and the grinding mill is thus avoided and the circulatin liquid is constantly at or near the point of its greatest Having thus described In invention and a simple illustrative metho of carryin it into effect it will be readily understood t at as stated hereinbefore the construction and arrangement of the operating parts of feed- -regulating appliance may be varied with- 'out departing from the spirit of the inven-.

tion as defined in the following claims.

1. The combination with a classifier having mechanism for conveying the oversize of divided material'to a point of discharge, of means regulating the feed to the classifier by a resistance of the oversize to the operation of said mechanism.

2. The combination'with a classifier having mechanism for conveying the oversize of divided material to a point of discharge,

of means regulating the feed to the classifier in proportion to the resistance of the oversize to the operation of said mechanism.

3. The combination with a classifier having mechanism for conveying the oversize of divided material to a point of discharge, of means reducing the feed to the classifier in proportion to the resistance of the oversize to the operation of said mechanism after said resistance has increased beyond a predetermined degree.

4. The combination-with a settling chamber having an outlet for settling matter, and

mechanism for moving settled matter to her having said outlet, of a feeding-appliance, and means operated by a resistance to the operation of saidmechanism to regulate the feed by said appliance.

5. The combination with a settling chamber having an outlet for settling matter, and mechanism for moving settled matter to said outlet, of a feedin appliance, and means regulating the feed y said appliance in proportion to the resistance of settled matter to the operation of said mechanism.

6. The combination with a settling chaman outlet for settled matter, of a feedmg-appliance, and means regulating the feed by said appliance by the movement of settled matter to said outlet.

7. The combination with a classifier connectedin a closed circuit, of means regulating'the-feed to said circuit by a resistance of the oversize of divided material, to its movement in the circuit.

8; In combination, a settling chamber having an outlet for settling matter, mech anism for moving settled matter to said outlet, an element in driving connection with said mechanism, and means regulating the feed to the settling-chamber by a resistance to the driving action of said element.

9. In combination,

outlet, an element in drlving connection with said mechanism, and means actuated by an increase of resistance to the driving action of said element, beyond a predetermined degree, to regulate the feed to the settling chamber.

10. In combination, a settling chamber having an outlet for settling matter, mechanism for moving settled matter to said out let, a feeding appliance, an element for the operation of said appliance, and means actuated by a resistance to the operation of said mechanism to regulate the driving action of said element.

In testimony whereof I have aflixed my signature in presence of two witnesses.

ALFRED L. BLOMFIELD.

Witnesses:

G. J. ROILANDET, L. RHOADES.

a settling chamber having an outlet for settling matter, mechanism for moving settled matter to said 

